Pneumatic rock drilling machine



March 13, 1934.

E. RYD 1,951,065 PNEUMATIC ROCK DRILLING MACHINE Filed Oct. 3, 1931 2Sheats-$heet 1 March 13, 1934. E. RYD 1,951,065

PNEUMATIC ROCK DRILLING MACHINE Filed Oct. 3, 1931 2 Sheets-Sheet 2 Z LW in said cylinder.

Patented Mar. 13, 1934 PNEoMATio noon DRILLING MACHINE Erik Ryd,Stockholm,

Sweden, assignor to Aktiebolaget Atlas Diesel, Stockholm, SwedenApplication October 3, 1931,. Serial No. 566,760 In Sweden September 12,1930 17 Claims.

The present invention relates to pneumatic rock drilling machines of thestoper type in which the feeding device consists of a stationary aircylinder and a feeding piston movable In pneumatic rock chillingmachines attempts have been made to construct automatically operatedfeeding devices. These attempts, however, were made upon drifters, thatis, machines which are supported by a shell and fed on guides, usuallyby means of a screw. Rock drilling machines of this type are very heavyand it not possible for one single man to manipulate the machine when itshall be moved from one bore-hole to another. The result of theoperation of such machines was uneconomical because the working capacityof the laborers necessary for the moving of the machine between thebore-holes could not be entirely utilized during the drilling.

The main object of the present invention is to produce a pneumatic rockdrilling machine which makes it possible to reduce the greatest expenseitem of rock drilling to a minimum by reducing the amount of labornecessary for the drilling.

A further object of the invention is to produce a pneumatic rocltdrilling machine in which the consumption of air under pressure isreduced.

Further objects will appear in the following specification and in theclaims.

According to the present invention pneumatic rock drilling machines ofthe stoper type are combined with a change-over valve which is adaptedto automatically effect the reversal of the feeding device at a definitepoint of the advancing movement. Said change-over valve is operated bymeans of the driving medium of the machine, and may also be adapted tothrottle the supply of the driving medium to the striking mechanismduring the returning movement of the machine.

The invention will be more fully described with reference to the annexeddrawings, in which:

1 shows one embodiment of the invention in longitudinal section andFigs. 2 and 3 sections on the broken lines II1I and III-Jillrespectively, in F g. 1, showing details of the changeover means. Fig. lshows the same section as 3, but in another setting position. Fig. 5shows a section on the broken line VV in Fig. l, but in another settingposition. Fig. 6 shows the change-over means and adjacent parts of themachine, in the same section as Fig. 1, but on a larger scale. Fig. 7shows the same section as Fig. 6, but in another setting position.

Referring now to Fig. l of the drawings the machine consists in awell-known manner, of a cylinder or casing l for the striking mechanismand a piston 2 which is movable in said cylin er and, by an intermediatepiece 3, operates ti tool 4; in the tool-holder. The tool or thetool-holder may be rotated in any suitable w'eihlinown manner notillustrated. The movement of the piston is regulated by an oscillatingslide-valve 5 of well-known construction, provided in a valve box 6which on one side carries the cylinder and on the other side a pistonrod 7. This rod is provided at its outer end with a piston '78 snuglyfitting in the feeding cylinder 79 which is attached to the frame of themachine in a suitable manner and at its foremost end is finished by abox 16 having packing means to form a seal around the piston rod.

According to the invention a rotatable cock plug 11 provided in thevalve box 6 at right angles to the longitudinal direction of themachine, said plug having a bore 12 open at the one end and connecteddirectly to the supply conduit 8 attached by means of a nut 9. In saidbore 12 reciprocates a sleeve shaped changeover slide valve 13. When thevalve 13 occupies the lower position, that is the position shown inFigs. 1 and 6, a channel 14 leading to the regulating valve 5 for thestriking mechanism is open, and so is also a channel 15 leading to acentral bore 16 provided in the piston rod 7 and discharging into thatportion of the cylinder chamber which lies behind the feeding piston 78,that is on the advancing or feeding side of the piston.

The portion of the cylinder chamber lying in front of the feedingpiston, that is the returning side, is connected on one hand to theatmosphere by an outlet channel 7 in the piston rod, said channelcommunicating via an aperture 18 in the valve box 6 (Figs. 1 and 6) witha recess 19 between the rotatable plug 11 and the change-over slidevalve 13 which, in its turn, communicates with the atmosphere through anaperture 20 in the valve box (Fig. 2). On the other hand the returningside of the feeding piston is connected through a channel 21, anaperture 22 in the valve box and a groove 23 having an aperture 24 inthe rotatable plug to an intermediate space 25 between said plug and thelower end side of the change-over valve, which space is separated fromthe bore in the change-over valve by a central pin projecting into saidvalve. Thus, the normal atmospheric pressure prevails in the space 25 asa result of the connection to the outlet channel 17, when the rotatableplug 11 is opened for supplying the driving medium to the regulatingvalve of the striking mechanism.

When the change-over valve occupies the advancing or feeding positionshown in Figs. 1 and 6, the driving medium passes through the upperportion of the bore 12, partly to the reg u:-

lating valve 5 of the striking mechanism and partly through the channel15, 16 to the advancing side of the piston 78 which in this way will beforced forwards at the same time as the machine is started. The air inthe cylinder chamber in the front of the piston thereby escapesthroughthe channel 1'7. When the opening of this channel passes in under thefront end wall.

of the cylinder chamber, formed by the box 10, said chamber will bedisconnected from the atmosphere. Subsequently this foremost cylinderchamber is brought into communication with the cylinder chamber behindthe piston 78 through a by-pass conduit 26 provided in the box 10. Thedriving medium flowing in through the channel 16 consequently will passthrough the channel 26, the channel 21, discharging closely by thepiston 78, the channel 22, the groove 23 and the aperture 24, to thespace 25 beneath the valve 13. Thus, the channels 15, 16, 26, 21, 22,the groove 23, and the aperture 24 form a by-pass conduit between thetwo end sides of the valve 13. Because the end side of the valve 13,facing this space 25 is formed with a greater area than that of the endside facing the supply conduit 8, said valve will be displaced to itsreturning position by the driving medium flowing in from the channel 21.c

When the change-over valve 13 is in its returning position, shown inFig. '7, it will cut off the supply to the regulating valve 5 and to thechannel 16 and close the aperture 18 which is connected to the outletchannel 17. In this position the lower end of a channel 27, closedduring the advancing movement, is open, said channel being provided inthe central pin projecting from the bottom of the rotatable plug intothe change-over valve. The driving'medium will then pass through thischannel 27 into the recess 19 in the rotatable plug beneath the valve,and further through the aperture 22 into the channel 21 to the cylinderchamber in front of the feeding piston '78 which thereby will be movedbackwards. The air in the cylinder chamber behind the piston then flowsout through the channels 16 and 15, a groove 28 in the rotatable plugpassing round the change-over valve, and flows through the channel 14leading to the regulating valve. When the machine is entirely returnedto its rear-most position the rotatable plug 11 will be turned by handto the position shown in Figs. 4 and 5. In this position the groove 23is in connection with the channel 29 discharging into the atmosphere, sothat the intermediate space 25 will be emptied and the change-over valvewill be returned to its advancing position due to the action of thedriving medium flowing in through the supply conduit 8. Further, in saidposition (Fig, 5) the supply is cut off to the channels 14 and 15. Byturning the rotatable plug 11 back to its initial position (Fig. 3) theoriginal conditions may be restored to start the striking and advancingmechanisms again.

In order to make it possible to stop the advancing movement and thestriking mechanism atany movement during said movement a manuallyoperated pin 30 is slidable in the rotatable plug and arranged in suchmanner, that by moving the same inwards the change-over valve 13 may beactuated and brought to its returning position, when desired.

It is understood that the invention is not restricted to the embodimentsdescribed and illustrated. Particularly the change-over member as Wellas the advancing and returning channels connected thereto may bearranged in many different ways. Further, the invention is applicable toall types of pneumatic rock drilling machines independent of theconstruction of the striking mechanism.

What I claim is:

1. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a supplyconduit connected to said cylinder for thedriving medium of the machine,and a change-over valve in said conduit operated by means of the drivingmedium and adapted to. reverse said feeding piston automatically at adefinite position of the advancing movement of said piston for returningsaid striking mechanism to -its initial position.

2. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a supplyconduit connected to said cylinder for the driving medium of themachine, a change-over valve in said conduit operated by means of thedriving medium and adapted to reverse said feeding piston automaticallyat a definite position of the advancing movement of said piston forreturning said striking mechanism to its initial position, and amanually operated rotatable cock plug controlling the supply of thedriving medium to said change-over valve and to said striking mechanism.

3. In a pneumatic rock drilling machine, a striking mechanism, a.stationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a supplyconduit connected to said cylinder for the driving medium of themachine, a change-over valve in said conduit operated by means of thedriving medium and adapted to reverse said feeding piston automaticallyat a definite position of the advancing movement of said piston forreturning said striking mechanism to its initial position, and amanually operated rotatable cock plug controlling the supply of thedriving medium to said change-over valve and to said striking mechanism,said plug forming a casing for said change-over valve.

4. In a pneumatic rock. drilling machine, a striking, mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost endto said striking mechanism, a supply conduitconnected to said cylinder for the driving medium of the machine, and achange-over valve in said conduit operated by means of the drivingmedium and adapted to reverse said feeding piston automatically at adefinite position of the advancing movement of said piston for returningsaid striking mechanism to its initial position and also adapted tothrottle the supply of the driving medium to said striking mechanismduring the returning movement of the same.

5. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end tosaid striking mechanism, a supply conduitconnected to said cylinder for the driving medium of the machine, achange-over valve in said conduit operated by means of. the drivingmedium and adapted to reverse. said feeding piston automatically at adefinite position of the advancing movement of said piston for returningsaid striking mechanism to its intial position, and, in additionthereto, a manually operated means for actuating said change-over memberto reverse said feeding piston to its initial position when desired.

6. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a supplyconduit connected to said cylinder for the driving medium of themachine, a change-over valve in said conduit adapted to reverse saidfeeding piston, said valve having two oppositely disposed surfaces, aby-pass channel between said two surfaces connected with said supplyconduit and adapted to be controlled by said feeding piston for changingover said valve automaticallly by means of the driving medium at adefinite position of the advancing movement of said feeding piston.

7. In a pneumatic r ck drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a casingbetween said feeding piston and said striking mechanism, a valve in saidcasing movable between two end positions, said valve having a large anda small surface on opposite sides thereof, a supply conduit for saiddriving medium connected with said casing at the small surface of saidvalve, one of the end positions of said valve allowing the drivingmedium to flow in at this small surface to advance said feeding piston,and a by-pass conduit between said surfaces adapted to be opened by saidfeeding piston when said piston has completed its advancing movement, tosupply the driving medium to said large surface for changing over saidvalve to the other of its end positions causing the driving medium toreturn said feeding piston.

8. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a casingbetween said feedingpiston and said striking mechanism, channels fromsaid casing to the advancing side and to the returning side of saidpiston, a valve in said casing movable between two end positions toconnect said channels alternately with a supply conduit for the drivingmedium and the atmosphere, one small surface on said valve at the inletof said supply conduit into said casing, an opposite large surface onsaid valve, and a by-pass conduit between said surfaces of the valveadapted to be opened by said feeding piston when said feeding piston hascompleted its advancing movement in relation to said cylinder, to supplysaid driving medium to said greater surface for changing over saidvalve.

9. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a casingbetween said feeding piston and said striking mechanism, a supplyconduit for the driving medium connected with said casing, channels fromsaid casing to the advancing side and to the returning side of saidpiston, a valve in said casing movable between two end positions toconnect said channels alternately with said supply conduit and theatmosphere, said valve having a small surface at the inlet of saidsupply conduit into said casing, said casing having an opening at thesame side of said valve as said small surface controlled by said valveand leading to said striking mechanism, said valve having an oppositelydisposed large surface, and a by-pass conduit between said surfaces ofthe valve adapted to be opened by said feeding piston, when said feedingpiston has completed its advancing movement in relation to saidcylinder, to supply said driving medium to said large surface forchanging over said valve.

10. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a casingbetween said feeding piston and said striking mechanism, a supplyconduit for the driving medium connected with said casing, channels fromsaid casing to the advancing side and to the returning side of saidpiston, a valve in said casing movable between two end positions toconnect said channels alternately with said supply conduit and theatmosphere, said valve having a small surface at the inlet of saidsupply conduit into said casing and an oppositely disposed largesurface, a by-pass conduit in said cylinder to connect the two sides ofsaid piston, when the latter has finished its advancing movement inrelation to said cylinder, and a further channel from the returning sideof said piston to said large surface to supply said driving medium tosaid large surface for changing over said valve, when said by-passconduit is opened.

11. in a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a housingbetween said feeding piston and said striking mechanism, in said housinga manually rotatable cock plug in the shape of a casing, a supplyconduit for the driving medium connected with said plug, channels fromsaid housing to the advancing side and to the returning side of saidpiston, said housing having an opening leading to said strikingmechanism, apertures in said plug registering with said channels andsaid opening in one position of said plug, in said plug a valve slidablebetween two end positions to connect said channels alternately with saidsupply conduit and the atmosphere and also to connect said opening tosaid striking mechanism with said supply conduit, when said plug is insaid registering position, said valve having a small surface at theinlet of said supply conduit into said plug and an oppositely disposedlarge surface, said surface communicating with said returning side insaid registering position of said plug and communicating with theatmosphere after said plug has been turned, and a by-pass conduit insaid cylinder to connect the two sides of said piston, when the latterhas finished its advancing movement in relation to said cylinder, tosupply said driving medium to said large surface for changing over saidvalve, when said by-pass conduit thus is opened.

12. In a pneumatic rock drilling machine, a striking mechanism, astationary cylinder, a feeding piston movable in said cylinder andattached at its foremost end to said striking mechanism, a housingbetween said feeding piston and said striking mechanism, in said housinga manually rotatable cock plug in the shape of a casing, a supplyconduit for the driving medium connected with said plug, channels fromsaid housing to the advancing side and to the returning side of saidpiston, said housing having an opening leading to said strikingmechanism, said plug having apertures, registering with said channelsand said opening in one position of said plug, in said plug a valveslidable between two end positions to connect said channels alternatelywith said supply conduit and the atmos-' phere and also to connect saidopening to said striking mechanism with said supply conduit, when saidplug is in said registering position, said valve having a small surfaceat the inlet of said supply conduit into said plug and an oppositelydisposed large surface, said large surface communicating with saidreturning side in said registering position of said plug andcommunicating with the atmosphere after said plug has been turned, aby-pass conduit in said cylinder to connect the two sides of saidpiston, whenthe latter has finished its advancing movement in relationto said cylinder, to supply the driving medium to said large surface forchanging over said valve, when said by-pass conduit thus is opened; anda manually operated pin slidable in said plug and adapted to move saidchangeover member to' its returning position, when desired.

13. In a pneumatic rock drilling machine, a striking mechanism, afeeding device comprising a cylinder and a piston, one of these twoparts of said device being stationary and the other being movable andattached to said striking mechanism, a supply conduit connected to saidcylinder for the driving medium of the machine, and a change-over valvein said conduit operated by means of the driving medium and adapted toreverse said feeding device automatically at a definite position of theadvancing movement of said feeding device for returning said strikingmechanism to its initial position.

14. In a pneumatic rock drilling machine, a striking mechanism, afeeding device comprising a cylinder and a piston, one of these twoparts of said device being stationary and the other part being movableand attached to said striking mechanism, a supply conduit connected tosaid cylinder for the driving medium of the machine, and a change-overvalve in said conduit operated by means of the driving medium andadapted to reverse said feeding: device automatically at a definiteposition of the advancing movement of said feeding device for returningsaid striking mechanism to its initialposition and also adapted tothrottle the supply of the driving medium to said striking mechanismduring the returning movement of the'same.

15. In a pneumatic rock drilling-machine, a striking mechanism, acylinder, a feeding piston in said cylinder, a casing, a supply conduitfor the driving medium connected with said casing, channels'from saidcasing to the advancing side and to the returning side of said piston,-avalve in said casing movable between two end positions to connect saidchannels alternately with said supply conduit and the atmosphere, onesmaller surface on said valve at the inlet of said supply conduit intosaid casing, in said casing at the same side of said valvea's saidsmaller surface an opening controlled by said valve and leading to saidstriking mechanism, an opposite greater surface on said valve, a by-passconduit from'said advancing side of said piston to said greater surface,and means for opening said by-pass conduit, when said feeding piston hascompleted its advancing movement in relation to said cylinder, to supplysaid driving medium to said greater surface for changing over saidvalve.

16. In a pneumatic rock drilling machine, a striking mechanism, acylinder, a feeding piston in said cylinder, a housing secured to saidpiston, in said housing a rotatable plug, a supply conduit for thedriving medium connected With said plug, channels from said housing tothe advancing side' and to' the returning side of said piston, anopening in said housing leading to said striking mechanism, apertures insaid plug registering witlrsaid-channels and said opening in oneposition of said plug," said plug serving as a casing for a valve"slidable between two end positions to connectsaid channels alternatelywith said supply conduit and the atmosphere and also to connect saidopening to said striking mechanism with said suplpy conduit, when saidplug is in said registering position, one smaller surface on said valveat the inlet of said supply conduit into said plug, an opposite greatersurface on said valve, communicating Withsaid returning side in saidregistering position of said plug and communicating with the atmosphere,after said plug has been turned, and a by-pass" conduit in said cylinderto connect the two sides of said piston, when the latter has finishedits advancing movement in relation to said cylinder, to supply saiddriving medium to said greater surface for changing over said valve,when said by-pass conduit thus is opened;

17. In a pneumatic rock drilling machine, a striking mechanism, acylinder, a feeding piston in said cylinder, a housing secured to saidpiston, in said housing a rotatable plug, a'

supply conduit for the driving medium con nected with said plug,channels from said housing to the advancing side and to the returningside of said piston, anop'ening in said housing leading to said strikingmechanism, apertures in said plug registering with said channels andsaid opening in one position of said plug, said plug serving as a casingfor a valve slidable between two end positions to connect said channelsalternately with said supply conduit and the atmosphere and also toconnect said opening to said striking mechanism with said supplyconduit, when said plug is in said registering position, one smallersurface on said valve at the inlet of said supply conduit-"into saidplug, an opposite greater surface on'said valve, communicating with saidreturning side in said registering position of said plug andcommunc'atin'g with the atmosphere, after said plug has been turned, abypass conduit in said cylinder to connect the two sides" of saidpiston, when the latter has finished its advancing movement in" relationto said cylinder, to supply said driving medium to said greatersurface'for changing over said valve, when said by-pass conduit thus isopened, and a manua-lly operated pin slidable in said plug and adaptedto move said change-over member to its returning position, when desired.

ERIK RYD.

